Mechanism of density inversion formation in partially molten rocks

This paper addresses the problem of the interpretation of geochemical laboratory experiments aimed at investigating partially molten rocks. The material of the terrestrial planets is differentiated at a certain stage of their evolution. In a gravity field, heavy and light particles move in a melt in different directions. This results in the formation of layers with different chemical and petrographic compositions in laboratory experiments and in planetary interiors. A density inversion appears in these layers under certain conditions. The dynamics of partially molten rocks was investigated using two analytical models. One of them is a problem of two bodies in a liquid governed by hydrodynamic Stokes equations. The second model describes the relative motion of solid particles in different directions in a viscous porous layer.